Efficacy, effectiveness, and behavior change trials in exercise research

Abstract Background The widespread incorporation of behavioral support interventions into exercise trials has sometimes caused confusion concerning the primary purpose of a trial. The purpose of the present paper is to offer some conceptual and methodological distinctions among three types of exercise trials with a view towards improving their design, conduct, reporting, and interpretation. Discussion Exercise trials can be divided into "health outcome trials" or "behavior change trials" based on their primary outcome. Health outcome trials can be further divided into efficacy and effectiveness trials based on their potential for dissemination into practice. Exercise efficacy trials may achieve high levels of exercise adherence by supervising the exercise over a short intervention period ("traditional" exercise efficacy trials) or by the adoption of an extensive behavioral support intervention designed to accommodate unsupervised exercise and/or an extended intervention period ("contemporary" exercise efficacy trials). Exercise effectiveness trials may emanate from the desire to test exercise interventions with proven efficacy ("traditional" exercise effectiveness trials) or the desire to test behavioral support interventions with proven feasibility ("contemporary" exercise effectiveness trials). Efficacy, effectiveness, and behavior change trials often differ in terms of their primary and secondary outcomes, theoretical models adopted, selection of participants, nature of the exercise and comparison interventions, nature of the behavioral support intervention, sample size calculation, and interpretation of trial results. Summary Exercise researchers are encouraged to clarify the primary purpose of their trial to facilitate its design, conduct, and interpretation.</p

Feasibility and preliminary efficacy of an online intervention to increase physical activity in Nova Scotian cancer survivors: A Randomized Controlled Trial

Background: Physical activity (PA) behavior change interventions among cancer survivors have used face-to-face, telephone, email, and print-based methods. However, computer-tailored, Internet-delivered programs may be a more viable option to achieve PA behavior change. Objective: The objective of this study is to test the feasibility and preliminary efficacy of a Web-based PA behavior change program among cancer survivors. Methods: Nova Scotian cancer survivors (N=415) who previously expressed interest in a research study were approached. Interested participants were asked to complete an online assessment of PA and quality of life (QOL) before being randomized to either a theory-based PA behavior change program using the PA tracking website UWALK (UCAN; n=48) or usual care (UC; n=47). After the intervention (9 weeks), participants completed another online assessment of PA and QOL as well as measures to evaluate the program and website. Descriptive analyses from surveys and Web analytic software were used to assess feasibility and mean change scores were used to test efficacy. Results: Of all contacted survivors, 95 (22.3%, 95/415) completed baseline measures and were randomized with 84 (88%, 84/95) completing the 9-week assessment. The behavior change program and website were rated highly on the satisfaction items. Average logins were 10.3 (1.1 per week) and 26.0% (111/432) of the weekly modules were completed. Most participants (71%, 29/41) indicated they were more aware of their daily PA levels and 68% (28/41) found the site easily navigable. Adjusted group differences in total exercise minutes favored the UCAN group by an increase of 42 minutes (95% CI -65 to 150; P=.44, d=0.17). Results were more pronounced, though still nonsignificant, among those not meeting guidelines at baseline where UCAN increased PA by 52 minutes compared to a decrease of 15 minutes in UC (adjusted between group difference=75, 95% CI -95 to 244; P=.38, d=0.27). Conclusions: We found that Internet-delivery may be a feasible alternative to more costly methods to promote PA among Nova Scotian cancer survivors. Moreover, there was a trend toward increased PA among those in the UCAN group, especially among those who were not meeting PA guidelines at baseline. Future research should focus on recruiting inactive cancer survivors and engaging them in the website to determine the optimal potential of Web-based interventions for promoting PA in cancer survivors

Diabetes NetPLAY: A physical activity website and linked email counselling randomized intervention for individuals with type 2 diabetes

<p>Abstract</p> <p>Background -</p> <p>This pilot study evaluated the feasibility (<it>recruitment, retention, adherence and satisfaction</it>) and preliminary efficacy of a 12-week website and email-linked counselling intervention on physical activity behaviour change in individuals with type 2 diabetes.</p> <p>Methods -</p> <p>A total of 49 individuals with type 2 diabetes (59% female, average age 54.1 years) were randomized to the Diabetes NetPLAY intervention or control condition. The intervention condition received information grounded in the Social Cognitive Theory (SCT), personalized weekly emails, an on-line logbook and message board. Key outcomes included physical activity behaviour and related cognition changes. The control condition was provided links to the Canadian Diabetes Association's Clinical Practice Guidelines for Physical Activity and Canada's Guide to Physical Activity.</p> <p>Results -</p> <p>Intervention participants indicated high levels of satisfaction for this mode of delivery and study results demonstrated the feasibility of web-based mediums for the delivery of physical activity information in this population. The intervention group demonstrated a significant improvement in total vigorous and moderate minutes of physical activity (p = 0.05) compared to the control group over the 12-week study. Among the SCT variables, behavioural capacity, showed a significant increase (p < 0.001) among intervention participants.</p> <p>Conclusion -</p> <p>Web-based interventions for individuals with type 2 diabetes are feasible and show promise for improving positive physical activity outcomes.</p

Determinants of quality of life in adults with type 1 and type 2 diabetes

Limited evidence exists on the determinants of quality of life (QoL) specific to adults with type 1 diabetes (T1D). Further, it appears no study has compared the determinants of QoL between T1D and type 2 diabetes (T2D) groups. The objectives of this study were to examine: (1) determinants of QoL in adults with T1D; and, (2) differences in QoL determinants between T1D and T2D groups. The Alberta Longitudinal Exercise and Diabetes Research Advancement (ALEXANDRA) study, a longitudinal study of adults with diabetes in Alberta, Canada. Adults (18 years and older) with T1D (N = 490) and T2D (N = 1,147) provided information on demographics (gender, marital status, education, and annual income), personality (activity trait), medical factors (diabetes duration, insulin use, number of comorbidities, and body mass index), lifestyle behaviors (smoking habits, physical activity, and diet), health-related quality of life (HRQL) and life satisfaction. Multiple regression models identified determinants of HRQL and life satisfaction in adults with T1D. These determinants were compared with determinants for T2D adults reported in a previous study from this population data set. Factors significantly associated with HRQL and life satisfaction in either T1D or T2D groups were further tested for interaction with diabetes type. In adults with T1D, higher activity trait (personality) score (β = 0.28, p < 0.01), fewer comorbidities (β = -0.27, p < 0.01), lower body mass index (BMI)(β = -0.12, p < 0.01), being a non-smoker (β = -0.14, p < 0.01), and higher physical activity levels (β = 0.16, p < 0.01) were associated with higher HRQL. Having a partner (β = 0.11, p < 0.05), high annual income (β = 0.16, p < 0.01), and high activity trait (personality) score (β = 0.27, p < 0.01) were significantly associated with higher life satisfaction. There was a significant age × diabetes type interaction for HRQL. The T2D group had a stronger positive relationship between advancing age and HRQL compared to the T1D group. No interaction was significant for life satisfaction. Health services should target medical and lifestyle factors and provide support for T1D adults to increase their QoL. Additional social support for socioeconomically disadvantaged individuals living with this disease may be warranted. Health practitioners should also be aware that age has different effects on QoL between T1D and T2D adults

Prediction of leisure-time walking: an integration of social cognitive, perceived environmental, and personality factors

<p>Abstract</p> <p>Background</p> <p>Walking is the primary focus of population-based physical activity initiatives but a theoretical understanding of this behaviour is still elusive. The purpose of this study was to integrate personality, the perceived environment, and planning into a theory of planned behaviour (TPB) framework to predict leisure-time walking.</p> <p>Methods</p> <p>Participants were a random sample (N = 358) of Canadian adults who completed measures of the TPB, planning, perceived neighbourhood environment, and personality at Time 1 and self-reported walking behaviour two months later.</p> <p>Results</p> <p>Analyses using structural equation modelling provided evidence that leisure-time walking is largely predicted by intention (standardized effect = .42) with an additional independent contribution from proximity to neighbourhood retail shops (standardized effect = .18). Intention, in turn, was predicted by attitudes toward walking and perceived behavioural control. Effects of perceived neighbourhood aesthetics and walking infrastructure on walking were mediated through attitudes and intention. Moderated regression analysis showed that the intention-walking relationship was moderated by conscientiousness and proximity to neighbourhood recreation facilities but not planning.</p> <p>Conclusion</p> <p>Overall, walking behaviour is theoretically complex but may best be addressed at a population level by facilitating strong intentions in a receptive environment even though individual differences may persist.</p

Aerobic physical activity and resistance training: an application of the theory of planned behavior among adults with type 2 diabetes in a random, national sample of Canadians

<p>Abstract</p> <p>Background</p> <p>Aerobic physical activity (PA) and resistance training are paramount in the treatment and management of type 2 diabetes (T2D), but few studies have examined the determinants of both types of exercise in the same sample.</p> <p>Objective</p> <p>The primary purpose was to investigate the utility of the Theory of Planned Behavior (TPB) in explaining aerobic PA and resistance training in a population sample of T2D adults.</p> <p>Methods</p> <p>A total of 244 individuals were recruited through a random national sample which was created by generating a random list of household phone numbers. The list was proportionate to the actual number of household telephone numbers for each Canadian province (with the exception of Quebec). These individuals completed self-report TPB constructs of attitude, subjective norm, perceived behavioral control and intention, and a 3-month follow-up that assessed aerobic PA and resistance training.</p> <p>Results</p> <p>TPB explained 10% and 8% of the variance respectively for aerobic PA and resistance training; and accounted for 39% and 45% of the variance respectively for aerobic PA and resistance training intentions.</p> <p>Conclusion</p> <p>These results may guide the development of appropriate PA interventions for aerobic PA and resistance training based on the TPB.</p

A test of cognitive mediation in a 12-month physical activity workplace intervention: does it explain behaviour change in women?

Background: Attempts to demonstrate the efficacy of interventions aimed at increasing physical activity (PA) have been mixed. Further, studies are seldom designed in a manner that facilitates the understanding of how or why a treatment is effective or ineffective and PA intervention designs should be guided by a heavier reliance upon behavioral theory. The use of a mediating variable framework offers a systematic methodological approach to testing the role of theory, and could also identify the effectiveness of specific intervention components. The primary purpose of this paper was to test the mediating role that cognitive constructs may have played in regards to the positive effect that a workplace behavioral intervention had on leisure-time PA for women. A subsidiary purpose was to examine the cross-sectional relationships of these cognitive constructs with PA behavior. Methods: The Physical Activity Workplace Study was a randomized controlled trial which compared the effects of stage-matched and standard print materials upon self-reported leisure-time PA, within a workplace sample at 6 and 12-months. In this secondary analysis we examined the mediation effects of 14 psychosocial constructs across 3 major social-cognitive theories which were operationalized for the intervention materials and measured at baseline, 6 and 12-months. We examined change in PA and change in the psychological constructs employing a mediation strategy proposed by Baron and Kenny for: (1) the first 6-months (i.e., initial change), (2) the second 6-months (i.e., delayed change), and (3) the entire 12-months (overall change) of the study on 323 women (n = 213 control/standard materials group; n = 110 stage-matched materials group). Results: Of the 14 constructs and 42 tests (including initial, delayed and overall change) two positive results were identified (i.e., overall change in pros, initial change in experiential powerful intervention approaches processes), with very small effect sizes. However, these mediating results were eliminated after adjusting for the multiple statistical tests. Conclusions: The intervention did not change these mediators in any substantive way, and show a similar pattern to prior research where interventions generally do not result in a change in mediation of behavior change. It is important to report mediation results in randomized controlled trials whether the findings are null or positive. Future studies may wish to focus on more detailed dose-response issues between mediators and behavior, the inclusion of moderators that could affect individual change, or different mediator constructs at higher levels of measurement specificity. Continued work on innovative and more powerful PA intervention approaches are needed

Physical Activity and Survival After Prostate Cancer

AbstractBackgroundDespite the high global prevalence of prostate cancer (PCa), few epidemiologic studies have assessed physical activity in relation to PCa survival.ObjectiveTo evaluate different types, intensities, and timing of physical activity relative to PCa survival.Design, setting, and participantsA prospective study was conducted in Alberta, Canada, in a cohort of 830 stage II–IV incident PCa cases diagnosed between 1997 and 2000 with follow-up to 2014 (up to 17 yr). Prediagnosis lifetime activity was self-reported at diagnosis. Postdiagnosis activity was self-reported up to three times during follow-up.Outcome measurements and statistical analysisCox proportional hazards models related physical activity to all-cause and PCa-specific deaths and to first recurrence/progression of PCa.Results and limitationsA total of 458 deaths, 170 PCa-specific deaths, and, after first follow-up, 239 first recurrences/progressions occurred. Postdiagnosis total activity (>119 vs ≤42 metabolic equivalent [MET]-hours/week per year) was associated with a significantly lower all-cause mortality risk (hazard ratio [HR]: 0.58; 95% confidence interval [CI], 0.42–0.79; p value for trend <0.01). Postdiagnosis recreational activity (>26 vs ≤4 MET-hours/week per year) was associated with a significantly lower PCa-specific mortality risk (HR: 0.56; 95% CI, 0.35–0.90; p value for trend = 0.01). Sustained recreational activity before and after diagnosis (>18–20 vs <7–8 MET-hours/week per year) was associated with a lower risk of all-cause mortality (HR: 0.66; 95% CI, 0.49–0.88). Limitations included generalisability to healthier cases and an observational study design.ConclusionsThese findings support emerging recommendations to increase physical activity after the diagnosis of PCa and would inform a future exercise intervention trial examining PCa outcomes.Patient summaryIn a 17-yr prostate cancer (PCa) survival study, men who survived at least 2 yr who were more physically active postdiagnosis or performed more recreational physical activity before and after diagnosis survived longer. Recreational physical activity after diagnosis was associated with a lower risk of PCa death

Correlates of exercise motivation and behavior in a population-based sample of endometrial cancer survivors: an application of the Theory of Planned Behavior

<p>Abstract</p> <p>Background</p> <p>Despite evidence of the benefits of exercise in cancer survivors, exercise participation rates tend to decline after treatments. Few studies have examined the determinants of exercise in less common cancer sites. In this study, we examined medical, demographic, and social cognitive correlates of exercise in endometrial cancer survivors using the Theory of Planned Behavior (TPB).</p> <p>Methods</p> <p>A mailed survey was completed by 354 endometrial cancer survivors (1 to 10 years postdiagnosis) residing in Alberta, Canada. The study was cross-sectional. Exercise behavior was assessed using the Godin Leisure Time Exercise Questionnaire and the TPB constructs were assessed with standard self-report scales. Multiple regression analyses were used to determine the independent associations of the TPB constructs with intention and behavior.</p> <p>Results</p> <p>Chi-square analyses indicated that marital status (<it>p </it>= .003), income level (<it>p </it>= .013), and body mass index (BMI) (<it>p </it>= .020) were associated with exercise. The TPB explained 34.1% of the variance in exercise behavior with intention (<it>β </it>= .38, <it>p </it>< .001) and self-efficacy (<it>β </it>= .18, <it>p </it>= .029) being independent correlates. For intention, 38.3% of the variance was explained by the TPB with self-efficacy (<it>β </it>= .34, <it>p </it>< .001) and affective attitude (<it>β </it>= .30, <it>p </it>< .001) being the independent correlates. The TPB mediated the associations of marital status and BMI with exercise but not income level. Age and BMI moderated the associations of the TPB with intention and behavior.</p> <p>Conclusion</p> <p>The TPB may be a useful framework for understanding exercise in endometrial cancer survivors. Exercise behavior change interventions based on the TPB should be tested in this growing population.</p